DIAGNOSING HOSTA PROBLEMS
|Holes, notched or cut-leaves||Insects and molluscs. In warmer climates, black vine weevils commonly feed on edges. Other possible problems include cutworms and leaf-cutter bees.|
|Spots-tan to Brown-random||Fungal leaf spot. Remove severely infected leaves, minimize wet foliage|
|Spots, brown and clustered||Four-lined plant bug|
|Ringspots Mottling Deformity||Virus. Laboratory identification is needed to determine which type of virus, and needed management strategy.|
|Change in color||Sport virus|
|Blights Anthracnose||Leaf spots that expand down leaf veins and infect petioles. Use a handlens identify black fruiting bodies in lesion to confirm diagnosis.|
|Dead areas between veins||Foliar nematodes.|
|Scorch||Insufficient water Too much sun ‘Frances Williams’|
|Reduced Size||Inadequate water or fertilizer "weak cultivar" root rot|
|Reduced Number||Inadequate water or fertilizer "weak cultivar" root rot|
Hosta collapse after a few hard freezes in the fall.
Burrowing animal damage. Check roots.
Crown rot. Check for mycelial growth and "mustard seed-like" structures.
|Brown||Root rot. Laboratory diagnosis to determine which one is essential to management.|